Category:Constrained-random-phase approximation

The constrained random-phase approximation (CRPA) is a method that allows the calculation of the effective interaction parameter U, J, and J' for model Hamiltonians. The main idea is to neglect the screening effects of specific target states in the screened Coulomb interaction W of the GW method. The resulting partially screened Coulomb interaction is evaluated in a localized basis that spans the target space and is described by the model Hamiltonian. The target space is usually low-dimensional and therefore allows for the application of a higher-level theory, such as dynamical-mean-field theory (DMFT).

More information about CRPA is found on the following page:

Constrained–random-phase–approximation_formalism